Addition Of Lime Research Articles

Deep learning based detection of monkeypox virus using skin lesion images

As we set into the second half of 2022, the world is still recovering from the two-year COVID-19 pandemic. However, over the past three months, the outbreak of the Monkeypox Virus (MPV) has led to fifty-two thousand confirmed cases and over one hundred deaths. This caused the World Health Organisation to declare the outbreak a Public Health Emergency of International Concern (PHEIC). If this outbreak worsens, we could be looking at the Monkeypox virus causing the next global pandemic. As Monkeypox affects the human skin, the symptoms can be captured with regular imaging. Large samples of these images can be used as a training dataset for machine learning-based detection tools. Using a regular camera to capture the skin image of the infected person and running it against computer vision models is beneficial. In this research, we use deep learning to diagnose monkeypox from skin lesion images. Using a publicly available dataset, we tested the dataset on five pre-trained deep neural networks: GoogLeNet, Places365-GoogLeNet, SqueezeNet, AlexNet and ResNet-18. Hyperparameter was done to choose the best parameters. Performance metrics such as accuracy, precision, recall, f1-score and AUC were considered. Among the above models, ResNet18 was able to obtain the highest accuracy of 99.49%. The modified models obtained validation accuracies above 95%. The results prove that deep learning models such as the proposed model based on ResNet-18 can be deployed and can be crucial in battling the monkeypox virus. Since the used networks are optimized for efficiency, they can be used on performance limited devices such as smartphones with cameras. The addition of explainable artificial intelligence techniques LIME and GradCAM enables visual interpretation of the prediction made, helping health professionals using the model.

Investigation of the Effect of Filler on Cohesive Bond Strength of Asphalt Mastic Using Binder Bond Strength (BBS) Test

Water damage leads to spalling and loosening of asphalt pavement, which is ultimately due to a reduction in the bond strength of the asphalt mastic. The filler, as an important component of the asphalt mastic, has a great impact on the various properties of the asphalt mastic and even the asphalt mix itself. Therefore, it is important to study the influence of fillers on the performance of asphalt mastic. In this paper, the various properties of twelve types of fillers, including mineral powder, mineral powder partially replaced with cement, slaked lime, and recycled powder, and their effects on the bond strength of asphalt mastic are investigated. Binder bond strength (BBS) was used to evaluate the performance of the different asphalt mastics. The moisture resistance of the asphalt mastic was evaluated by measuring the bond strength of the asphalt mastic after treatment in a water bath. A grey correlation analysis was then carried out to derive the relationship between the filler index and the bond strength of the asphalt mastic. The results show that the addition of slaked lime and cement helped to improve the moisture resistance of the asphalt mastic. The fineness modulus and other indicators have a great influence on the bond strength of asphalt mastic. The interaction between hydrothermal coupling and filler type has a non-negligible effect on the moisture resistance of the asphalt mastic.

Evaluation of the Effect of Binary Fly Ash-Lime Mixture on the Bearing Capacity of Natural Soils: A Comparison with Two Conventional Stabilizers Lime and Portland Cement.

This study evaluates a binary mixture of fly ash and lime as a stabilizer for natural soils. A comparative analysis was performed on the effect on the bearing capacity of silty, sandy and clayey soils after the addition of lime and ordinary Portland cement as conventional stabilizers, and a non-conventional product of a binary mixture of fly ash and Ca(OH)2 called FLM. Laboratory tests were carried out to evaluate the effect of additions on the bearing capacity of stabilized soils by unconfined compressive strength (UCS). In addition, a mineralogical analysis to validate the presence of cementitious phases due to chemical reactions with FLM was performed. The highest UCS values were found in the soils that required the highest water demand for compaction. Thus, the silty soil added with FLM reached 10 MPa after 28 days of curing, which was in agreement with the analysis of the FLM pastes, where soil moistures higher than 20% showed the best mechanical characteristics. Furthermore, a 120 m long track was built with stabilized soil to evaluate its structural behavior for 10 months. An increase of 200% in the resilient modulus of the FLM-stabilized soils was identified, and a decrease of up to 50% in the roughness index of the FLM, lime (L) and Ordinary Portland Cement (OPC)-stabilized soils compared to the soil without addition, resulting in more functional surfaces.

Thermodynamic modelling of steelmaking slag to reduce refractory consumption during CONARC® process

ABSTRACT CONARC® steelmaking process which combines the basic oxygen and electric arc furnace steelmaking, requires precise operation and control of slag chemistry within an optimum range to reduce the refractory wear. The target slag should be MgO saturated, containing solid particles of magnesium wustite which ensures good foamy slag and causes less erosion of MgO-C refractory. In this present study, FactSage™ software was utilized to study and visualize the MgO saturation of slag through MgO-SiO2-FeO-CaO-Al2O3-MnO and CaO-SiO2-FeO-MgO-Al2O3-MnO systems. The ternary phase diagrams revealed, the slag was MgO-under saturated based on the current pattern of calcined lime and dolomite addition during the process. Based on the findings of this study, the addition pattern were altered to bring the slag regime within the MgO saturation level with good slag basicity. This change showed significant improvement in reducing the erosion rate of MgO-C lining in furnace and thereby reducing the specific gunning mass requirement.

Effect of liming and fertilizers on the growth and nutrition of 12-month old Teak (Tectona grandis L.) grown on acidic soil of Peru

Peru has a great potential for forestry plantations, nevertheless, importations of this type of products are getting very expensive. Soils under forest are acidic and infertile to support sustainable economically valuable forest tree species such as teak. Information is lacking on proper fertility management in forest plantations such as teak. Therefore, the objective of this study was to explore the effect of lime, and organic and inorganic fertilizers on the early growth and nutrient composition of 12-month old teak grown on acidic soil of Peru. The soil under field study was acidic with a pH of 4.99, low in fertility. A factorial design of 2x3: Lime (No Lime and Liming) and fertilizer (organic, inorganic and mixture), with 9 repetitions was adopted. Tree biometric parameters (height, diameter, biomass) and N, P, K, Ca, Mg, Fe, Cu, Mn, Zn foliar concentrations were determined during early the growth of teak. Treatments with addition of dolomite lime favored higher biometric parameters, and use of organic fertilizers promoted more growth than inorganic fertilizers. In the case of nutrients, no major differences were observed between limed and unlimed treatments while organic fertilizer promoted Ca, K and S nutrition. The results show that the application of lime and organic fertilizers is essential for the successful management and establishment of teak plants in acidic soils of Peru.

CO2-Minimized Ferrochrome Production Utilizing Silicon Wafer Cutting Slurry as an Alternative Reductant

Direct emissions due to the use of carbon-based fossil-reducing agents contribute to the overall CO2 emissions of pyrometallurgical production processes. This study investigated the replacement of fossil coke by silicon-rich cutting waste from the solar wafer cutting process to produce ferrochrome in an electric arc furnace. Laboratory test work and thermochemical simulation were carried out to examine the product quality at various additions of cutting waste and lime. The experimental trials resulted in products in accord with international standards, however, adjusting the slag composition by the addition of lime was necessary, otherwise high silicon contents in the alloys were obtained. Due to the highly exothermic reaction of silicon with iron- and chromium oxides, the silicothermic reduction results in a decreased specific electric energy consumption compared to the carbothermic reduction according to the thermochemical simulation. Low phosphorus and sulfur contents in the alloy might result in premium prices, aiding the economic viability of the process.Graphical

Assessment of Pollution Status of River Ajali in Enugu State Using water quality index

The physico-chemical and microbial examination of Ajali River in Ezeagu Local Government Area (LGA) of Enugu State, South-eastern Nigeria, were carried out to assess the characteristics of the water for potability. Water samples were collected from three sampling points, including the one close to the brewery effluent discharge into the river and two different points that were affected by non-point sources. Altogether, eighteen samples were collected for two years during the dry, early and late rainy seasons. The physico-chemical, as well as microbial analyses of the samples, were determined following the standard methods. Significant spatial and seasonal variations (p<0.05) were clear for some physico-chemical parameters such as pH, phosphate, and sodium. Mean values of the Water Quality Index (WQI) were: dry season (104.23±9.75); early rainy season (113.22±8.78) and the late rainy season (102.58 ± 11.15). All the values are above 100 showing that the calculated WQI in all the seasons is not good however after the addition of lime, boiling and filtering to increase the quality.

Examining the use of Lime and Gypsum in GGBS based alkali activated concrete

Alkali Activated Concrete (AAC) using Ground Granulated Blast Furnace Slag (GGBS) and Fly ash as precursors attracted several researchers in developing no cement concretes. Use of Fly ash as precursor needs high temperature for curing. GGBS as precursor avoids temperature curing, but setting is too fast to accept or compare with conventional or ordinary Portland Cement. Many researchers have used the combination of GGBS and Fly ash as precursor in developing AAC. Lime resources are plentily available, and use of lime be encouraged for developing sustainable concretes. Thus, an attempt has been made to examine the use of lime to some extent in the AAC. The present paper examines the use of lime and gypsum along with GGBS and metakaolin as precursor in developing AAC. 4 M Sodium hydroxide and sodium silicate solution is used as alkaline activator. Consistency, setting times and compressive strength of these mixes are reported. It is found that lime and gypsum addition has increased the consistency as well as setting times. It is suggested that precursor with 75% GGBS, 20% Metakaolin and 5% Lime showed good compressive strength. Addition of gypsum lowered the compressive strength of the mix.

Pembuatan VCO (Virgin Coconut Oil) Dengan Penambahan Ekstrak Jeruk Nipis (Citrus aurantifolia swingle), Bawang Putih (Allium Sativum), dan Ragi Tape (Saccharomyces Cerevisiae) Secara Fermentasi dan Pengasaman

The manufacture of Virgin Coconut Oil (VCO) which is done by heating is considered less effective because the quality of VCO produced is not good and also requires expensive production costs. Virgin Coconut Oil (VCO) is a processed product from coconut that has many benefits if processed properly, which is one of the reasons VCO has a promising target market, so further research needs to be done on the process of making VCO so that it can produce quality products. This study aims to determine the effect of the addition of garlic extract (Allium sativum), lime (Citrus aurantifolia swingle), and yeast tape (Saccharomyces cerevisiae) on Virgin Coconut Oil (VCO) products and to know the process of making VCO simply by fermentation and acidification to save production costs. Fermentation is the process of making VCO using the help of bacteria, in this study used Saccharomyces cerevisiae, while the manufacture of VCO by acidification is the manufacture of VCO with the addition of acidic substances, in this study used lime. The processing of VCO by fermentation or acidification in this study does not go through a stirring process, but is allowed to stand for 8-10 hours until three layers are formed, namely water, oil, and blondo which will then be separated to obtain the desired product (VCO). The addition of garlic extract in the process of making VCO by fermentation is thought to be able to eliminate the rancid odor in the resulting product, this is proven to be true after the results obtained from the VCO manufacturing process show that VCO given the addition of garlic extract does not smell rancid but a little smell of garlic mixed with delicious savory coconut. Overall, making VCO by fermentation using tape yeast, adding garlic extract, and acidification using lime produces VCO products that are clear in color and do not smell rancid so that the results of VCO can be categorized as good. In addition to the conventional process that is often done, making VCO can also be done by fermentation and acidification as done by researchers. In the process of making VCO by acidification, researchers need to ensure that the pH is in an appropriate state.

Liming and micronutrient application improves soil properties and productivity of the groundnut‐rapeseed cropping system in an acidic Inceptisol of India's eastern Himalayas

AbstractAluminum toxicity, nutrient imbalance, and reduced microbial activity are the most limiting factors for optimum agronomic productivity in acid soils. A field study was conducted to investigate the impact of micronutrient and liming on soil properties and productivity of groundnut‐rapeseed system in an acidic Inceptisol. The impact of six micronutrient (control or no micronutrient, Zn at 5 kg ha−1, B at 1 kg ha−1, Mo at 0.5 kg ha−1, Zn + Mo, and Zn + B + Mo) and two soil amendment (furrow liming at 500 kg ha−1 and no lime addition) treatments were first tested in groundnut and theirs residual effects were assessed on soil properties of succeeding rapeseed crop. Results indicated that liming significantly improved soil pH, soil organic carbon (SOC), available N, P and K, and diethylene triamine penta acetate (DTPA)‐extractable micronutrients, soil microbial biomass C and dehydrogenase activity as compared to no‐lime. After harvesting groundnut, Mo + Zn + B treated plots maintained the highest SOC content, whereas sole B and Mo treatment had the highest SOC content after harvesting rapeseed. Further, Mo + Zn + B treated plots showed higher contents of soil DTPA‐extractable micronutrients as compared to others. The highest groundnut equivalent yield (GEY) of the cropping system (pooled data of 2 years) was obtained with Mo + Zn + B (2.12 Mg ha−1) but remained at par with Zn + Mo (2.02 Mg ha−1). Multivariate principal component analysis indicated that available P was the most prominent soil nutrient with a strong effect on GEY. The results indicated that integrated application of Zn + B + Mo along with liming improves soil properties and agronomic productivity of groundnut‐rapeseed cropping system.

Dissolved inorganic and organic carbon export from tile-drained midwestern agricultural systems

While carbon is a critically important natural element cycling through the soil profile of agricultural systems, few studies have examined the flux of dissolved organic carbon (OC) and inorganic carbon (IC) through artificially-drained cropped fields. In this study, we monitored eight tile outlets, nine groundwater wells and the receiving stream during a March to November period in 2018 to quantify subsurface IC and OC flux from tiles and groundwater to a perennial stream from a single cropped field in north-central Iowa. Results showed that carbon export from the field was dominated by IC losses through subsurface drainage tiles that were 20× higher than dissolved OC concentration in tiles, groundwater and in Hardin Creek. IC loads from tiles comprised approximately 96 % of the total carbon export. Detailed soil sampling within the field quantified TC stocks to a 1.2 m depth (246,514 kg/ha), and based on the maximum annual rate of IC loss from the field (553 kg/ha per year), we estimated that approximately 0.23 % of the TC content (0.32 % of the TOC content and 0.70 % of the TIC content) of the shallow soils was lost in a single year. Loss of dissolved carbon from the field is likely offset by reduced tillage and additions of lime. Study results suggest that attention should be given to improved monitoring of aqueous total carbon export from fields for accurate accounting of carbon sequestration performance.

Swelling of sulfate-bearing soil: A case study of A1 highway pavement failure

Lime stabilization is one of the most commonly used methods for improving weak road subgrades, but it becomes very problematic in sulfate-bearing soils. This article presents results of a case study in which the sulfate attack was the most probable reason for a significant deformation of a highway pavement founded on lime-stabilized Doggerian clay. Macroscopic analysis revealed partial degradation of the concrete structure, a larger extent of stabilization than designed, and large gypsum crystals in the native soil. Chemical tests indicated a very high content of sulfates in the soil (> 10,000 mg/kg of SO4) and in the groundwater (> 3,000 mg/l of SO42-). The maximum free swelling strain (εvolmax = 3–6%) and the swelling pressure (pcmax = 56 kPa) of the clay, determined in the Wasiliew apparatus and the oedometer tests, were not large enough to be considered as the only cause of the pavement damage. Sand-cement and clay-lime mixtures, which simulated stabilized soil layers in the road profile, were observed for several months in oedometric tests, under various loading conditions. The swelling of Sa-Cem was negligible, but the Cl-Lim mixtures turned out to be much more expansive than the natural soil (εvolmax up to 21%, pcmax = 230 kPa) with a much longer duration of volume increase. The samples were flooded with distilled water or hard groundwater to clarify whether the constant access of the material to sulfates is important in the swelling process, but the results were unequivocal. X-ray diffraction revealed that the addition of lime resulted in the formation of secondary minerals: butlerite, portlandite, and ettringite. The presence and swelling of ettringite in the stabilized sub-base soil layers was eventually agreed to be the most probable reason for the pavement deformation. These results indicate the need to introduce an obligatory investigation of the level of sulfates in clayey subbase soils subject to lime stabilization.

Control Parameters for the Long-Term Tensile and Compressive Strength of Stabilized Sedimentary Silt

The yellow-layer soils of the Guabirotuba formation in Brazil are problematic due to their expansive nature and low-bearing capacity. There has been little exploration into stabilizing these soils using a calcium-based binder. In addition, existing methods for dosing lime to fine and coarse-grained soils using the porosity-to-lime index (η/Liv) have primarily focused on non-optimal compaction conditions to determine the split tensile and compressive strengths and empirical relationships between both tests while ignoring the study of optimal lime-soil mixes compaction conditions. Therefore, the objective of this research is to examine the unconfined compressive (qu) and split tensile (qt) behavior of a traditional Guabirotuba yellow silt stabilized with dolomitic hydrated lime (L) under standard, intermediate, and modified effort conditions and the correlation between qu and qt. The lime-soil blends were cured for up to 180 days, and 3-9% lime percentages were used under optimum compaction conditions (maximum dry density and optimum water content). The porosity/lime index (η/Liv), a semi-empirical index, was utilized to investigate the evolution of qu and qt over the short and long term. η/Livvaried between 6-25% by volume. Furthermore, the qt/qu index was calculated to be between 0.12-0.20, depending on the curing time, independent of lime addition and compaction effort used. Equations well-suited to a power function dosing qt and qu based on curing time and η/Livindex was proposed. Finally, some dosages of soil-lime mixtures were proposed for possible applications in geotechnical engineering, applying the porosity and volumetric binder index in optimal compaction conditions, which had not been applied before for lime-improved soils. Doi: 10.28991/CEJ-2023-09-04-03 Full Text: PDF

Cadmium Accumulation and Immobilization by Artemisia selengensis under Different Compound Amendments in Cadmium-Contaminated Soil

Cadmium (Cd) contamination is a global environmental challenge that threatens human food security. Lime combined with five different organic materials (rape seed cake, mushroom residue, straw, sawdust, and corn cobs) (LOM) at application ratios of 1:1 and lime sawdust combined with nitro-compound fertilizer (Ca(NO3)2·4H2O, KH2PO4, KNO3) (LSF) at different application rates were applied to Cd-contaminated soil. The present study investigates the effects of these organic–inorganic compound amendments on Cd bioavailability in soil, and Cd uptake and accumulation by edible Artemisia selengensis parts. A. selengensis was cultivated for three consecutive seasons in Cd-contaminated soil. LOM and LSF treatments obviously reduced the uptake and accumulation of Cd. Compared with the control soil, contents of Cd in edible parts of A. selengensis decreased by 19.26–33.33% and 26.67–32.78% in the first season, 18.60–32.79% and 18.37–32.79% in the second season, and 20.45–40.68% and 34.32–37.27% in the third season, respectively. The addition of Lime + Mushroom Residue and 70% Nitro-compound Fertilizer + Lime + Sawdust most significantly reduced Cd concentrations in the edible parts of the third A. selengensis season. LOM and LSF application increased soil pH and improved soil fertility, including available nitrogen, available phosphorus, available potassium, organic matter, and cation exchange capacity. Lime + Mushroom Residue improved plant yield the most. In addition, Lime + Mushroom Residue and 70% Nitro-compound Fertilizer + Lime + Sawdust had the lowest Cd accumulation and health risk indices, respectively. In conclusion, the Lime + Mushroom Residue and 70% Nitro-compound Fertilizer + Lime + Sawdust amendments significantly reduced health risks, enhanced A. selengensis growth, and promoted sustainable development of arable land under Cd-contaminated soil remediation.

Combined Utilization of Chinese Milk Vetch, Rice Straw, and Lime Reduces Soil Available Cd and Cd Accumulation in Rice Grains

Cadmium (Cd) pollution poses a growing threat to rice production in acidic paddies. In south China, a common agricultural practice involves the combined utilization of Chinese milk vetch (M) and rice straw (R). However, it is unclear how the addition of lime to these amendments affects Cd bioavailability and accumulation in soil. Control (CK), chemical fertilizer (F), Chinese milk vetch + rice straw + chemical fertilizer (MRF), and Chinese milk vetch + rice straw + chemical fertilizer + lime (MRFL) treatments were applied to develop a kind of green, efficient, and practical amendment for acidic paddies. We conducted a microplot experiment to explore Cd immobilization in paddy soil and the Cd content in rice grains with these treatments. The results showed that compared with F, the rice Cd in the MRF and MRFL treatments were significantly decreased by 51.7% and 65.2% in early rice and 23.0% and 43.3% in late rice, respectively. Both the MRF and MRFL treatments significantly reduced soil available Cd and weak acid-extractable cadmium (Aci-Cd) concentrations and increased soil organic matter (SOM), exchangeable cation concentrations, and pH, which converted Cd into a stable form in soil. In addition, the MRF and MRFL treatments increased soil pH value by reducing soil exchangeable hydrogen ion concentration (E-H). Additionally, recombination of Cd forms was the primary factor in the reduction in available Cd concentration according to partial least squares path modeling (PLS-PM) analysis. The Cd concentration of rice grains was primarily associated with soil available Cd, soil pH value, and SOM. Overall, these results provide useful data and novel insights into reducing rice grain Cd in south China.

Efektivitas Pengapuran dalam Meningkatkan Pertumbuhan dan Produksi Tanaman Sorgum (Sorghum bicolor (L.) Moench) sebagai Hijauan Pakan Ternak

&#x0D; Sorghum is a potential crop as feed forage. The objective of the research was to obtain optimum dose of liming to improve the growth and productivity of sorghum (Sorghum bicolor (L.) Moench) biomass as feed forage. A completely randomized design with 4 treatments and 4 replications were applied for the research. The treatments were doses of dolomite lime addition i.e., 1) SD0 (dolomite lime addition at a dose of 0 ton/ha) as a control, 2) SD1 (dolomite lime addition at a dose of 1 ton/ha), 3) SD2 (dolomite lime addition at a dose of 2 ton/ha), and 4) SD3 (dolomite lime addition at a dose of 3 ton/ha). The result shows that supplementation of dolomite lime at doses of 2‒3 tons ha-1 can increase soil pH after a week of incubation. The dolomite lime addition at a dose of 3 tons ha-1 significantly increases (P&lt;0.05) the plant height (2 weeks after planting) and the number of leaves from a week after planting until the end of the research (10 weeks after planting). In addition, this dose of dolomite addition (3 tons/ha) can increase fresh biomass productivity as well as dry biomass compared to control (SD0). In conclusion, supplementation of dolomite lime at a dose of 3 tons ha-1 was effective to increase the pH value of soil, plant height, leaves number, as well as fresh and dry biomass of sorghum plant. In addition, this dose of dolomite lime produces better green color of sorghum plant leaf compared to without liming.&#x0D; &#x0D; Keywords: biomass production, dolomite lime, feed forage, Sorghum bicolor (L.) Moench

Probing the Stochastic Unconfined Compressive Strength of Lime–RHA Mix Treated Clayey Soil

This study investigated the different geotechnical characteristics of soil stabilization with the addition of lime and rice husk ash (RHA) in varying amounts (3%, 5%, 7%, and 9% lime, and 4%, 8%, 12%, and 16% RHA). A series of compaction, unconfined compressive strength (UCS), California bearing ratio (CBR), pH, and X-ray diffraction (XRD) tests were performed in the laboratory to assess the impact of the considered admixtures on the stabilized soil parameters. This study also proposes the successful integration of an artificial neural network (ANN) and a Gaussian process regression (GPR) with the experimental UCS observations. The lime concentration, RHA concentration, and curing period were considered as the input parameters, and UCS was considered as the response. The proposed framework was extended to analyze the compressive behavior of treated soil on the minuscule level. Such coupled machine learning-based experimental investigation can provide deep insight into the soil behavior which otherwise would have remained unexplored due to the prohibitive nature of performing laboratory experiments on a large scale. The findings demonstrated the effectiveness of RHA in addition to lime in stabilizing the considered expansive soil. With the addition of lime and RHA mix, the UCS and CBR values of the treated soil increased significantly.

The effect of lime addition on weathering resistance and mechanical strength of gypsum plasters and renders

Despite historical evidence revealing the extensive use of gypsum-lime plasters and renders for interior, exterior and structural applications in many parts of the world, systematic studies of the effect of varying amounts of lime on the properties of these materials are rare. Here we studied the influence of lime addition (5–95 wt% quicklime) on porosity, compressive and flexural strength, surface hardness, water vapor permeability and weathering resistance of gypsum-lime plasters in relation to their mineralogical composition, phase distribution, and textural characteristics. Results showed that even small lime additions resulted in reduced strength, but compatible conservation materials can be easily designed to match the properties of original historic plasters and renders, which are normally debilitated through deterioration. Moreover, lime additions significantly improved weathering resistance, thus enabling a wider use (including exterior applications) of gypsum-lime plasters, which could replace currently used building materials with larger carbon footprint in new constructions.

Clay-free biodiesel-based drilling fluid suitable for high temperature

This paper introduces the formation of a clay-free biodiesel-based drilling fluid system. The system uses the biodiesel derived from the transesterification between soybean oil and methanol as the continuous phase, which is environmentally friendly and has an appropriate flow state. In order to inhibit the hydrolysis of the base oil under high temperatures, a small amount of methanol is retained and Lime addition is minimized. Besides, the system also contains a special polyamine-typed rheological modifier instead of organoclay to provide a fragile gel-structure with lower plastic viscosity and higher yield point, thus good for hole cleaning and solid suspension while keeping a higher rate of penetration (ROP). In order to strengthen the plugging and fluid loss control abilities, superfine calcium carbonate and oxidized asphalt are added and obtain a good outcome. Evaluation results showed that the clay-free biodiesel-based drilling fluid exhibits good properties of rheology, filtration, and emulsion stability, with temperature resistance over 200°C, which is suitable for the exploration of unconventional oil/gas restores.

Production of low phosphorous steel from low silicon high phosphorous hot metal in BOF

ABSTRACT Production of low phosphorous (≤0.015%) steel in Basic Oxygen Furnace (BOF) using high phosphorous (average 0.17%) and low silicon (≤0.5%) hot metal with Si/P ratio <3 is a challenging task. In addition to temperature, slag basicity and FeO, the quantity of slag becomes important which is achieved by higher lime addition. However, how much lime is appropriate need to be understood. A detailed analysis of plant data indicated that a scope exists for lowering lime addition from existing level. Accordingly, systematic trials were conducted with reduction in lime which showed that lowering 12% lime had no effect while 19% reduction increased end blow (EB) P by 20 ppm. SEM-EDX studies of slag samples revealed chemical and morphological changes in trial heats. Lime addition pattern was also found to impact EB P. Addition of lime in a small batch during 10–25% of the oxygen blow resulted lower EB P.